Differential glycosylation of murine B cell and spleen adherent cell Ia antigens.
Examination of I-A and I-E molecules from purified B cells and splenic adherent cells from various haplotypes revealed a consistent difference in isoelectric focusing (IEF) that has been localized to the alpha-chain. alpa-Chains from B cells appeared heterogeneous and contained acidic IEF bands absent from the adherent cell I-A molecules. No difference in Ia beta-chain or H-2 IEF patterns was observed when B cell and adherent cell preparatios were compared when B cell and adherent cell preparations were compared. I-A alpha-chain preparations from the 2 cell sources showed no differences in 3H-leucine-labeled tryptic peptides separated by reverse-phase high-pressure liquid chromatography. Digestion with neuraminidase, kinetics of labeling, and subcellular distribution indicated that the extra acidic IEF bands in B cell Ia represent a mature, more heavily sialated form of alpha-chain that is not present in adherent cells. The selective differential glycosylation of B cell and adherent cell Ia could have some relation to the function of those cell types or to cell type-specific recognition of those cells.
D000818:Animals; D000954:Antigens, Surface; D001402:B-Lymphocytes / Q000276:immunology*; D050260:Carbohydrate Metabolism; D002448:Cell Adhesion; D005455:Fluorescent Antibody Technique; D006023:Glycoproteins / Q000276:immunology; D000949:Histocompatibility Antigens Class II; D006863:Hydrogen-Ion Concentration; D007137:Immunoglobulin alpha-Chains; D007525:Isoelectric Focusing; D051379:Mice; D008805:Mice, Inbred A; D009439:Neuraminidase / Q000494:pharmacology; D012794:Sialic Acids / Q000494:pharmacology; D013154:Spleen / Q000276:immunology*
D000954:Antigens, Surface; D006023:Glycoproteins; D000949:Histocompatibility Antigens Class II; D007137:Immunoglobulin alpha-Chains; D012794:Sialic Acids; D009439:Neuraminidase